Chocolate Chip Butterscotch Cake Recipe

Preheat the oven to 350F/177C convection (325F/163C conventional) and grease four 6" pans (or three 8-9").
In a stand mixer with the whisk attachment, combine the butter, oil, granulated sugar, and light brown sugar on medium speed. Add in the vanilla and eggs, one at time, beating for a minute after each.
1 cup (226g) unsalted butter softened, 1/3 cup (80ml) canola oil, 1 cup (200g) granulated sugar, 1 cup (220g) light brown sugar lightly packed, 2 tsp (10ml) vanilla, 5 large eggs room temperature
Combine the flour, salt and baking powder. Add the flour mixture into the butter mixture by alternating with the buttermilk, beginning and ending with the dry ingredients. Beat just until the flour is fully incorporated.
3 cup (360g) cake flour spooned and leveled, 1/2 tsp salt, 2 tsp (10g baking powder, 1 cup (240ml) buttermilk
Mix 1 Tbsp of flour with the chocolate chips (to prevent them from sinking in the batter) and then fold the chocolate chips into the batter.
2 cup (340g) mini chocolate chips + 1 Tbsp (8g) flour
Distribute the batter evenly between the pans and bake for 30 minutes, until golden brown. Remove them from the pans and allow them to cool completely before frosting.

Melt the butter over medium-high heat. Add in the sugar and heavy cream and mix until everything is fully combined.
1/2 cup (113g) unsalted butter, 1 cup (220g) light brown sugar lightly packed, 1 cup (240ml) heavy cream
Bring the mixture to a boil and then lower the heat to low-medium for 4-5 minutes. Remove the butterscotch from the heat and stir in the vanilla and salt. Cover it and allow it to cool to room temperature.
1 tsp (5ml) vanilla, 1/2 tsp salt

Heat the cream in a saucepan and remove it just before boiling. Pour in the chocolate chips, let it sit for a minute, and then stir until smooth. Allow it to cool to room temperature.
1/2 cup (120ml) heavy cream, 1 cup (175g) bittersweet chocolate chips
Beat the butter until it is pale and fluffy. Add in the sugar and cocoa powder and beat for 5-10 minutes until everything is fully dissolved and fluffy. Mix in the chocolate ganache, vanilla, and salt; beat for another few minutes. The color will continue to lighten the more you beat it.
1 cup (226g) unsalted butter softened, 1 1/2 cup (190g) powdered sugar spooned and leveled, 1/2 cup (50g) Dutch-process cocoa powder spooned and leveled, 1 tsp (5mL) vanilla, 1/4 tsp salt

Place the bottom cake layer on a cake stand/board. Pipe a rim of chocolate ganache icing around the edge of the cake to make a border. Spread a layer of butterscotch on the cake inside the 'rim'. Spread a layer of chocolate ganache icing and top with a little extra butterscotch .
Place the next layer of cake on top and repeat until all layers are used. Refrigerate the cake for 1-2 hours before using left over icing and butterscotch to frost the outside of the cake.
Bring to room temperature before serving. Enjoy!